Display device

Abstract

To provide a display that can improve efficiency of use of light source light.SOLUTION: A black matrix substrate (BM substrate) 10 is superimposed on an optical module 20 to form a display 100, and light sources of the optical module are controlled to display a screen. The BM substrate 10 includes black matrices (BM)131 and black stripes (BS)161, and the BS161 are arranged at positions closer to the optical module than the BM131. BS-side light reflecting films 162 are laminated on respective surfaces of the BS161 that face the optical module. Light reflecting films (BM-side light reflecting films) 131 are laminated, of light absorption zones extending in two directions of the BM131, on a surface of a light absorption zone facing the optical module and on which the BS161 are not laminated.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a display device. [Background technology]

[0002] The technology for displaying a screen using light emitted from a light source such as an LED is well known and is described in Patent Documents 1 to 3, for example.

[0003] However, the light utilization efficiency of the emitted light is not sufficient, and there is still room for improvement. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 2653014 [Patent Document 2] Japanese Patent Application Laid-Open No. 2000-321566 [Patent Document 3] International Publication No. 2020 / 115837 Summary of the Invention [Problem to be solved by the invention]

[0005] SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide a display device that can improve the efficiency of light utilization from a light source. [Means for solving the problem]

[0006] A display device according to a first aspect of the present invention is a display device configured by overlapping a black matrix substrate and an optical module, and controlling a light source of the optical module to display a screen, the black matrix substrate comprises a black matrix (BM) and a black stripe (BS), and the BS is disposed closer to the optical module than the BM; the BM has a shape in which light absorbing bands extending in two directions perpendicular to each other are arranged in a lattice pattern, and the openings thereof are pixel openings corresponding to pixels of a display screen; The BS has a shape in which optical absorption bands extending in a certain direction are arranged in parallel, and the direction in which the optical absorption bands extend coincides with one of two directions in which the BM extends, and both are overlapped in a positionally aligned manner; A light reflective film (BS-side light reflective film) is laminated on the surface of this BS on the optical module side, This display device is characterized in that, of the light absorbing bands extending in two directions of the BM, a light reflective film (BM-side light reflective film) is laminated on the optical module side surface of the light absorbing band that is not overlapped with the BS.

[0007] The display device according to the present invention can be a display device in which, among the light absorbing bands extending in two directions of the BM, the width of the light absorbing band on which the BS is superimposed is wider than the width of the BS.

[0008] The display device according to the present invention may be a display device in which the width of the BS-side light reflecting film is narrower than the width of the BS.

[0009] Furthermore, the display device according to the present invention can be a display device in which, among the light absorbing bands extending in two directions of the BM, the width of the BM-side light reflective film is narrower than that of the light absorbing band on which the BM-side light reflective film is laminated.

[0010] In the display device according to the present invention, the BS side light reflective film is formed through a titanium film or a titanium nitride film. The display device may be made of laminated thin metal films of aluminum or aluminum alloy.

[0011] Furthermore, the display device according to the present invention may be a display device in which the BS-side light-reflecting film has a three-layer structure, and the middle layer is made of a metal thin film of silver or a silver alloy.

[0012] The display device according to the present invention may be a display device in which the BM-side light-reflecting film is made of a metal thin film of aluminum or an aluminum alloy laminated via a titanium film or a titanium nitride film.

[0013] Furthermore, the display device according to the present invention may be a display device in which the BM-side light reflective film has a three-layer structure, and the middle layer is made of a metal thin film of silver or a silver alloy.

[0014] The display device according to the present invention may be a display device in which the black matrix substrate includes a transmittance adjusting layer on the viewer side of the BM.

[0015] The display device according to the present invention may be a display device in which the transmittance adjusting layer is made of a dispersion in which at least carbon is dispersed in a transparent resin.

[0016] The display device according to the present invention may be a display device in which the black matrix substrate includes a light scattering layer between the BM and the BS.

[0017] The display device according to the present invention may be a display device in which the light scattering layer is made of a dispersion of transparent particles, carbon, and a transparent resin.

[0018] The display device according to the present invention may be a display device in which the black matrix substrate includes a color filter layer that colors transmitted light.

[0019] The display device according to the present invention may be a display device in which a plurality of light-emitting elements are arranged inside the optical module.

[0020] The display device according to the present invention may be a display device in which the light emitting element is a light emitting element that emits monochromatic light of blue or near ultraviolet.

[0021] The display device according to the present invention may be a display device in which the light emitting element is an LED.

[0022] The display device according to the present invention may be a display device having a wavelength conversion layer between the light emitting element and the colored filter, the wavelength conversion layer converting light emitted from the light emitting element into green light or red light.

[0023] The display device according to the present invention can be a display device that includes a liquid crystal layer and a liquid crystal driving substrate between the black matrix substrate and the optical module, and drives the liquid crystal layer between the black matrix substrate and the liquid crystal driving substrate.

[0024] In the display device according to the present invention, the optical module is configured by arranging a plurality of light-emitting units, When the region of the display screen corresponding to a single light-emitting unit is defined as a display area, the display device may include a plurality of the pixel openings in this display area.

[0025] In the display device according to the present invention, the light emitting element is arranged in a 1:1 correspondence with the pixel opening. The display device may be a display device that includes a display unit. [Effects of the Invention]

[0026] According to the display device of the present invention, a BM and a BS are provided. A BS-side light-reflecting film is laminated on the optical module-side surface of the BS. Of the light-absorbing bands extending in two directions of the BM, a BM-side light-reflecting film is laminated on the optical module-side surface of the light-absorbing band not overlapped by the BM. Therefore, light source light from the light source of the optical module passes through the pixel openings to form pixels on the display screen, or is reflected by the BS-side light-reflecting film or the BM-side light-reflecting film and returns toward the optical module. Generally, the optical module has a light-reflective member on its opposite side to direct the generated light source light toward the desired direction. Therefore, the light source light reflected by the BS-side light-reflecting film or the BM-side light-reflecting film is reflected again toward the black matrix substrate. Therefore, theoretically, all light source light passes through the pixel openings and is used for screen display. This significantly improves the light utilization efficiency of the light source light. [Brief explanation of the drawings]

[0027] [Figure 1] FIG. 1 is an explanatory cross-sectional view of a display device according to a first embodiment of the present invention. [Figure 2] FIG. 2 is an explanatory cross-sectional view of the black matrix substrate according to the first embodiment of the present invention. [Figure 3] FIG. 3 is an explanatory graph illustrating the difference in reflectance depending on whether or not a transmittance adjusting layer is present according to the first embodiment of the present invention. [Figure 4] FIG. 4 relates to the first embodiment of the present invention and is an explanatory diagram for explaining the arrangement of pixel openings and black matrices. [Figure 5] FIG. 5 is an explanatory diagram for explaining the arrangement of pixel openings and black stripes according to the first embodiment of the present invention. [Figure 6] FIG. 6 is an explanatory diagram for explaining the arrangement of pixel openings, black matrices, and black stripes according to the first embodiment of the present invention. [Figure 7] FIG. 7 is a cross-sectional view for explaining an optical module according to the first embodiment of the present invention. [Figure 8] FIG. 8 is a circuit diagram of a drive circuit for a light emitting element of an optical module according to the first embodiment of the present invention. [Figure 9] FIG. 9 is an explanatory cross-sectional view of a display device according to a second embodiment of the present invention. [Figure 10] FIG. 10 is a cross-sectional view illustrating a light emitting element of an optical module according to a second embodiment of the present invention. [Figure 11] FIG. 11 is an explanatory cross-sectional view of a display device according to a third embodiment of the present invention. [Figure 12] FIG. 12 is an explanatory cross-sectional view of a black matrix substrate according to a third embodiment of the present invention. [Figure 13] FIG. 13 is an explanatory diagram for explaining the arrangement of pixel apertures colored in each color and a black matrix according to a third embodiment of the present invention. [Figure 14]FIG. 14 is an explanatory diagram for explaining the arrangement of pixel openings colored in each color and black stripes according to the third embodiment of the present invention. [Figure 15] FIG. 15 is an explanatory diagram for explaining the arrangement of pixel apertures colored in various colors, black matrices, and black stripes according to the third embodiment of the present invention. [Figure 16] FIG. 16 is an explanatory cross-sectional view of a display device according to a fourth embodiment of the present invention. [Figure 17] FIG. 17 is an explanatory cross-sectional view of a liquid crystal driving substrate according to a fourth embodiment of the present invention. [Figure 18] FIG. 18 is a circuit diagram of a drive circuit for thin film transistors of a liquid crystal drive substrate according to a fourth embodiment of the present invention. [Figure 19] FIG. 19 is an explanatory cross-sectional view of a display device according to a fifth embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0028] [First embodiment] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings, in which: Fig. 1 is an explanatory cross-sectional view of a display device according to a first embodiment of the present invention;

[0029] As shown in FIG. 1, the display device 100 of the first embodiment includes a black matrix substrate (BM substrate) 10 and an optical module 20 as its components.

[0030] The BM substrate 10 and the optical module 20 that constitute the display device 100 will be described in detail later. First, the relationship between these elements and the operating principle of the liquid crystal display device 100 will be outlined.

[0031] First, the optical module 20 is a device that generates display light necessary for the screen display of the display device 100. For this reason, the optical module 20 is configured by arranging a plurality of light-emitting elements 23. These plurality of light-emitting elements 23 are configured by blue-emitting LEDs.

[0032] The optical module 20 includes a wavelength conversion layer 20RG, and the light source light generated by the light emitting element 23 first enters this wavelength conversion layer 20RG. The wavelength conversion layer 20RG contains wavelength conversion particles that convert the incident blue light to red light and wavelength conversion particles that convert the incident blue light to green light. Therefore, the light that passes through this wavelength conversion layer 20RG becomes pseudo-white light that is a mixture of blue, red, and green light, and this pseudo-white light is emitted from the optical module 20.

[0033] Next, this pseudo white light is incident on the BM substrate 10. The BM substrate 10 is provided with a lattice-shaped black matrix (BM) 131, whose openings (pixel openings) Px correspond to the pixels of the display screen. The pseudo white light that passes through these pixel openings Px is then displayed on the screen as display light.

[0034] The plurality of light-emitting elements 23 correspond one-to-one to the pixel openings Px, and when one of the plurality of light-emitting elements 23 is lit, the light source light emitted from the lit light-emitting element 23 passes through the corresponding pixel opening Px and illuminates one pixel on the display screen. On the other hand, when one light-emitting element is turned off, the corresponding pixel remains dark. Therefore, by controlling whether or not each of the plurality of light-emitting elements 23 is lit, a screen display can be performed.

[0035] In addition to the BM 131, the BM substrate 10 is provided with a black stripe (BS) 161.

[0036] As mentioned above, the BM131 has a shape in which light-absorbing bands extending in two mutually perpendicular directions are arranged in a lattice pattern. In this example, the two directions in which the light-absorbing bands extend are designated as the X direction and the Y direction, respectively. The X direction is the left-right direction in the figure. On the other hand, the Y direction is the direction from the front to the back of the figure.

[0037] On the other hand, BS161 has a shape in which optical absorption bands extending in a certain direction are arranged in parallel. The direction in which this BS161 extends coincides with one of the two directions (X direction and Y direction) in which the BM131 extends. In this example, the direction in which BS161 extends is the Y direction. The BS161 and the optical absorption band of BM131 extending in the Y direction are aligned and overlapped with each other.

[0038] A light reflective film (BS-side light reflective film) 162 is laminated on the surface of the BS 161 on the side of the optical module 20. In addition, among the light absorbing bands extending in the two directions of the BM 131, the light absorbing bands on which the BS 161 is not overlapped (i.e., the light absorbing bands extending in the X direction) are optical modules. A light reflecting film (BM side light reflecting film) 132 is laminated on the surface on the 20 side.

[0039] Of the light source light emitted from the optical module 20, light that enters the pixel opening Px of the BM 131 is used for screen display, but light that enters the BS-side light reflecting film 162 is reflected and returns toward the optical module 20. In addition, light that enters the BM-side light reflecting film 132 is also reflected and returns toward the optical module 20.

[0040] Generally, the optical module 20 is provided with a light-reflecting member on the opposite side so that the generated light source light is emitted in a desired direction. Therefore, the light reflected by the BS-side light-reflecting film 162 or the BM-side light-reflecting film 132 is reflected again and directed toward the BM substrate 10.

[0041] Therefore, this light-reflective member and the BS-side light-reflecting film 162 and the BM-side light-reflecting film 132 face each other across the light-emitting element 23, and therefore the light source light generated from the light-emitting element 23 is reflected between them many times, with the result that substantially all of the light source light is emitted from the pixel opening Px of the BM. Then, the light source light emitted from the pixel opening Px is used for screen display, thereby improving light utilization efficiency.

[0042] Next, the BM substrate 10 and the optical module 20 will be described in detail separately.

[0043] (BM substrate 10) FIG. 2 is a cross-sectional view for explaining the BM substrate 10 in the first embodiment of the present invention.

[0044] As can be seen from this FIG. 2, the BM substrate 10 includes a transparent substrate (the transparent substrate of the BM substrate) 11, a transmittance adjustment layer 12, a BM 131, a light scattering layer 14, a flattening layer 15, a BS 161, a BS-side light reflection film 162, and a transparent resin layer 17. In addition, it also includes a BM-side light reflection film 132 that does not appear in this figure.

[0045] (The transparent substrate 11 of the BM substrate) The transparent substrate 11 of the BM substrate is a transparent substrate through which the display light emitted from the display device 100 transmits toward the observer, and its surface constitutes the display screen. As the transparent substrate 11 of the BM substrate, for example, a glass substrate, a quartz substrate, a sapphire substrate, or a plastic substrate such as a polyester film or a polyimide film can be used. The higher the transmittance of visible light, the more preferable. For example, the transmittance of the transparent substrate 11 of the BM substrate may be 50% or more and 100% or less, and more preferably 90% or more and 100% or less.

[0046] (The transmittance adjustment layer 12) The transmittance adjustment layer 12 scatters the display light emitted from the optical module 20 and transmitted through the pixel openings Px of the BM 131 in a paper-white-like manner, improving visibility and widening the viewing angle. Additionally, the transmittance adjustment layer 12 absorbs or scatters ambient light incident on the display device 100 from the display screen side, thereby preventing re-reflected light generated by specular reflection of this ambient light from becoming noise and reducing the contrast of the display screen. To perform these functions, the transmittance adjustment layer 12 is preferably disposed between the transparent substrate 11 and the BM 131 of the BM substrate. More preferably, the transmittance adjustment layer 12 is disposed at the interface between the transparent substrate 11 and the BM 131 of the BM substrate so that the transparent substrate 11, the transmittance adjustment layer 12, and the BM 131 of the BM substrate are in contact with each other. In this example, the transmittance adjustment layer 12 is disposed at the interface between the transparent substrate 11 and the BM 131 of the BM substrate.

[0047] In order to absorb ambient light incident on the liquid crystal display device 100, the transmittance of the transmittance adjusting layer 12 for visible light is preferably set in the range of 70% to 99.7%.

[0048] When ambient light enters the display device 100 from the transparent substrate 11 side of the BM substrate, the ambient light passes through the transmittance adjustment layer 12 once, is reflected by a light-reflective member inside the display device 100, and then passes through the transmittance adjustment layer 12 again to be emitted toward the viewer. In this way, the ambient light passes through the transmittance adjustment layer 12 twice to be emitted from the display device 100. Of the reflected ambient light, the amount of light that can be emitted to the outside is the amount of incident light multiplied by the square of the transmittance of the transmittance adjustment layer 12, so the emitted reflected ambient light is significantly attenuated compared to when the transmittance adjustment layer 12 is not provided.

[0049] For example, if the visible light transmittance of the transmittance adjusting layer 12 is 70%, this corresponds to the reflectance of the internal light reflective member being substantially 49%.

[0050] Such a transmittance adjusting layer 12 can be formed by blending carbon black, which absorbs incident ambient light, into a resin and applying the blend to the transparent substrate 11 of the color filter substrate. By adding 0.2 to 8 wt% of carbon black to the resin solid content and applying the layer to a thickness of 0.1 to 1 μm, it is possible to set the visible light transmittance of the transmittance adjusting layer 12 to a range of 70% to 99.7%.

[0051] When carbon black is not blended into the transmittance adjusting layer 12, the ambient light reflected at the interface between the transmittance adjusting layer 12 and BM131 may appear yellowish. In contrast, when carbon black is blended into the transmittance adjusting layer 12, no coloring is observed in the reflected light.

[0052] The resin that can be used for this transmittance adjusting layer 12 may be any resin that can provide the necessary reliability, such as heat resistance. An alkali-developable photosensitive resin or a thermosetting resin may be used. The thermosetting resin may be, for example, an epoxy group-containing compound or resin, or a resin having at least one group selected from a methylol group, an alkoxymethyl group, or an acyloxymethyl group.

[0053] Fig. 3 is an explanatory graph illustrating the difference in reflectance depending on whether or not there is a transmittance adjusting layer 12. That is, Fig. 3(a) shows the reflectance when the transmittance adjusting layer 12 is disposed at the interface between the transparent substrate 11 of the BM substrate and the BM 131. This transmittance adjusting layer 12 is formed by applying a resin containing carbon black. On the other hand, Fig. 3(b) shows the reflectance when the transparent substrate 11 of the BM substrate and the first black matrix 14 are disposed so as to be in direct contact with each other, without disposing the transmittance adjusting layer 12.

[0054] In addition to carbon black, transparent fine particles that scatter incident ambient light may be blended. As such transparent fine particles, for example, optically isotropic fine particles with an average primary particle diameter of 3 to 100 nm can be preferably used. For example, silicon oxide fine particles can be used.

[0055] In addition to these carbon blacks and transparent fine particles, an ultraviolet absorber and a small amount of blue pigment can also be blended.

[0056] As can be seen from FIG. 3(a), when a resin containing carbon black is applied to form the transmittance adjustment layer 12, the reflectance of the transmittance adjustment layer 12 increases when the wavelength exceeds 600 nm. On the other hand, when a small amount of blue pigment is blended to form the transmittance adjustment layer 12, the reflectance for light with a long wavelength of 600 nm or more can be reduced.

[0057] Examples of the ultraviolet absorber to be blended in the transmittance adjustment layer 12 include benzophenone-based compounds, benzotriazole-based compounds, and triazine-based compounds.

[0058] <BM131 and BM side light reflection film 13 BM131 has a shape in which light-absorbing bands extending in two mutually orthogonal directions are arranged in a lattice pattern. That is, in this example, it is composed of a light-absorbing band extending in the left-right direction (X direction) in the figure and a light-absorbing band extending in the direction from the front to the back of the figure (Y direction). And the openings of this lattice-shaped BM131 correspond to the pixels of the display screen. Therefore, in this specification, the openings of this lattice-shaped BM131 are referred to as "pixel openings Px".

[0059] This BM131 has a black color that absorbs visible light. Therefore, display light and ambient light incident between pixel opening Px and pixel opening Px are absorbed by this BM131. As described above, since the transmittance adjustment layer 12 is laminated on BM131, the reflected light on its surface is also small. And since there is no light emitted from the position Px between pixel opening Px and the pixel opening toward the display screen, a high-contrast screen display can be performed.

[0060] BM131 can be formed by dispersing black pigments with visible light absorption properties, such as carbon black or titanium black, in resin. In addition to these black pigments, organic pigments such as blue pigments can also be added. For example, BM131 can be formed by dispersing these pigments in a negative-tone photosensitive resin, applying the resin, and then exposing and developing it using photolithography technology.

[0061] Of the light absorbing bands extending in two directions of this BM 131, a BM-side light reflecting film 132 is laminated on the surface of the light absorbing band extending in the X direction, facing the optical module 20.

[0062] 2 shows a cross section of a portion without a light absorbing band extending in the X direction, and therefore the light absorbing band extending in the X direction and the BM-side light reflective film 132 laminated on the surface thereof do not appear in Fig. 2. On the other hand, Fig. 4 is an explanatory diagram showing the arrangement of the pixel openings Px and the BMs 131, and Fig. 4 also shows the BMs 131.

[0063] 4 shows pixel openings Px arranged in a matrix, and BM 131 is provided in a lattice pattern surrounding these pixel openings Px. Also shown is a state in which a BM-side light reflecting film 132 is laminated on the surface of the light absorbing band extending in the X direction, of the light absorbing bands extending in two directions of this BM 131, on the optical module 20 side.

[0064] In the figure, "131y" indicates the width of the light-absorbing band extending in the X direction, and "132y" indicates the width of the BM-side light-reflecting film 132 extending in the X direction. The width 132y of the BM-side light-reflecting film 132 is configured to be narrower than the width 131y of the light-absorbing band of the BM 131 extending in the X direction. If the width 132y is equal to the width 131y, the BM-side light-reflecting film 132 may be visible at the end of the BM 131 when the display screen is observed from an oblique direction. On the other hand, if the width 132y is narrower than the width 131y as shown here, the BM-side light-reflecting film 132 will not be visible even when the display screen is observed from an oblique direction, and a high-quality screen display can be achieved.

[0065] In the drawing, "131x" indicates the width of the light absorbing band extending in the Y direction among the light absorbing bands extending in two directions of the BM 131. This width 131x is configured to be wider than the width 161x of the BS 161, which will be described later.

[0066] The BM-side light-reflecting film 132 can be made of a light-reflecting metal thin film having a single-layer structure or a multi-layer structure.

[0067] The thickness of the BM side light reflective film 132 may be, for example, 0.15 to 0.8 μm. By setting the thickness to 0.15 μm or more, it is possible to eliminate light that passes through the BM side light reflective film 132. Therefore, the BM 131 does not need to have high light blocking properties. For example, an optical density in the range of 2 or more and 3 or less is sufficient.

[0068] The single-layer BM-side light-reflecting film 132 may be, for example, a metal thin film made of aluminum or an aluminum alloy. Examples of aluminum alloys that can be used include high-melting-point metals such as molybdenum and titanium, rare earth elements such as neodymium, and aluminum alloys containing a small amount of silicon. From the perspective of reflectivity, an aluminum alloy containing 0.2 to 3 mass% neodymium is preferred. If the neodymium content is less than 0.2 mass%, the aluminum crystals tend to become coarse or hillocks form, which can reduce the light reflectivity. Furthermore, if the neodymium content exceeds 3 mass%, the light reflectivity also tends to decrease. In contrast, a high reflectivity can be stably achieved when the neodymium content is in the range of 0.2 mass% to 3 mass%.

[0069] Alternatively, a silver or silver alloy metal thin film can be used as the single-layer BM-side light-reflecting film 132. When using such a silver or silver alloy metal thin film, it is preferable to use a three-layer BM-side light-reflecting film 132 with the silver or silver alloy metal thin film as an intermediate layer and conductive oxide thin films on both sides of the intermediate layer. A preferred conductive oxide thin film is a mixed oxide containing a first metal oxide material made of indium oxide and a second metal oxide material made of an oxide of a metal element that does not substantially have a solid solubility with silver. Examples of metal elements that do not substantially have a solid solubility with silver include titanium, zirconium, tantalum, niobium, hafnium, cerium, bismuth, germanium, silicon, and chromium. Alternatively, a composite oxide of indium oxide, zinc oxide, or tin oxide can be used as the conductive oxide.

[0070] These thin films can also be stacked with a titanium nitride thin film or a titanium thin film between them and the BM131.

[0071] The BM side light reflecting film 132 can be formed by using a vacuum film forming method such as vacuum deposition or sputtering.

[0072] The patterning can be performed using a known patterning technique, for example, by using a lift-off technique, first printing a paste or resin that dissolves in an aqueous or alkaline solution in a pattern, then vacuum-forming the metal thin film on this patterned printed film, and finally applying an aqueous or alkaline solution to dissolve and remove the patterned printed film and the metal thin film that was overlaid on the patterned printed film, thereby achieving patterning.

[0073] Patterning can also be performed using photolithography. That is, a photosensitive resin is applied to a vacuum-formed metal thin film, exposed and developed, and then the metal thin film is etched using the remaining photosensitive resin as a resist, thereby patterning the desired shape. As mentioned above, if the BM-side light-reflecting film 132 uses a thin conductive oxide film made of a composite oxide of indium oxide, zinc oxide, and tin oxide, the etching rate of this conductive oxide thin film can be adjusted by changing the amount of zinc oxide.

[0074] <Light scattering layer 14> The light scattering layer 14 has the function of diffusing the light source light emitted from the optical module 20, thereby widening the viewing angle of the display screen.

[0075] In the first embodiment, the light scattering layer 14 is disposed between the BM 131 and the BS 161, but may be disposed at any position as long as the light source light emitted from the optical module 20 can be diffused.

[0076] The light-scattering layer 14 can be formed by blending transparent particles with a resin to form a coating liquid and then coating the coating liquid. A dispersion aid may also be blended. As will be described later, the light-scattering layer 14 can also be formed using two resins that have low compatibility and different refractive indices.

[0077] However, because the light-scattering layer 14 has the property of diffusing or scattering light, it is difficult to form another layer on this light-scattering layer 14 using photolithography. This is because the exposure light used in photolithography is reflected and scattered by the light-scattering layer 14, and this reflected and scattered light enters the photoresist as noise light and exposes it, reducing the exposure accuracy. Examples of another layer formed using photolithography include the BS 161 and the BS-side light-reflecting film 162.

[0078] Since the exposure light used in photolithography is generally ultraviolet light with a short wavelength, this exposure light can be absorbed and prevented from being reflected and scattered by blending an ultraviolet absorber into the light-scattering layer 14. When the light-scattering layer 14 is made using transparent particles, or when the light-scattering layer 14 is made using two types of resin with different refractive indices, it is possible to blend an ultraviolet absorber.

[0079] Therefore, when forming the light-scattering layer 14 using transparent particles, it is preferable to use particles with a particle diameter larger than the wavelength of visible light as the transparent particles used in the light-scattering layer 14. Particles with a particle diameter similar to the wavelength of the visible light to be scattered have high transmittance to the visible light to be scattered, and are less likely to cause light scattering. In contrast, when particles with a particle diameter larger than the wavelength of visible light are used, the transmittance to visible light decreases and high light scattering is exhibited.

[0080] For these reasons, the transparent particles preferably have an average particle size of 1.0 to 3.0 μm, and the dispersion aid may also contain transparent fine particles with an average particle size of about 0.2 μm or 0.1 μm or less.

[0081] Furthermore, it is desirable that the transparent particles have a refractive index different from that of the resin contained in the light scattering layer 14. This is because light is scattered by reflection or refraction at the interface between the transparent particles and the resin, which have different refractive indices.

[0082] Examples of such transparent particles include inorganic particles such as silica particles and zinc oxide particles. Zinc oxide particles are preferred because they have high light scattering properties, high transmittance in the visible wavelength range of 400 to 700 nm, and the ability to absorb ultraviolet light of 390 nm or less. Organic particles such as acrylic resin, styrene resin, urethane resin, nylon, melamine resin, and benzoguanamine resin can also be used.

[0083] In display devices 103 and 104 that display a screen by driving the liquid crystal layer 30 pixel by pixel, as in the fourth and fifth embodiments described below, the transparent particles are preferably optically isotropic so as to maintain the polarization plane of the display light passing through the light-scattering layer 14 without rotating it. Examples of such optically isotropic inorganic particles include amorphous silica particles. Organic particles are generally isotropic.

[0084] Examples of the ultraviolet absorber include benzophenone-based compounds, benzotriazole-based compounds, and triazine-based compounds. The ultraviolet absorber preferably has a phenolic hydroxyl group. By providing the phenolic hydroxyl group, crosslinking with compounds having an alkoxymethyl group or a methylol group can be performed during heat treatment. Crosslinking can suppress bleeding of the ultraviolet absorber during long-term storage after hardening, thereby improving reliability. The amount of ultraviolet absorber added can be, for example, in the range of 0.05 to 10% by mass relative to the resin.

[0085] Because the light-scattering layer 14 is thus composed of a dispersion of transparent particles larger than the wavelength of light, its thickness is preferably greater than the average particle size of the transparent particles. For example, it is 1 to 50 μm. While it can be formed to a thickness greater than 50 μm, increasing the thickness does not significantly improve scattering properties. In fact, forming a thick layer increases the process load, such as wasted work time during coating and drying.

[0086] As described above, it is also possible to form a coating liquid by dissolving or dispersing a plurality of resins that have low compatibility and different refractive indices in a solvent, and after applying this coating liquid, to cause phase separation of these resins, thereby forming a layer with a sea-island structure having different refractive indices, and to use this layer as the light-scattering layer 14.

[0087] <Planarization layer 15> As described above, when the light scattering layer 14 contains transparent particles, irregularities based on the transparent particles are formed on its surface. The flattening layer 15 fills and flattens these irregularities and is formed by applying an optically transparent resin. By forming the BS161 and the BS side light reflection film 162 on such a flattened surface, they can be formed with high precision. When there are no irregularities on the surface of the light scattering layer 14, this flattening layer 15 is not required.

[0088] <BS161 and the BS side light reflection film 16 2> Next, as shown in FIG. 5, the BS161 has a shape in which light absorption bands extending in a certain direction are arranged in parallel. The extending direction is the same as the direction in which the light absorption band in which the BM side light reflection film 132 is not provided extends among the two light absorption bands extending in the two directions of the BM131. In this first embodiment, among the two light absorption bands extending in the two directions of the BM131, the BM side light reflection film 132 is provided on the light absorption band extending in the X direction, and the BM side light reflection film 132 is not provided on the light absorption band extending in the Y direction. Therefore, the BS161 extends in the Y direction.

[0089] When viewed from the display screen side, among the light absorption bands extending in the two directions of the BM131, the light absorption band extending in the Y direction and the light absorption band constituting the BS161 are positionally aligned and overlapped. Of course, the pitches of both are also the same.

[0090] Also, the BS side light reflection film 162 is laminated on the surface of the light module 20 side.

[0091] FIG. 6 is an explanatory diagram showing an array state including the positional relationship among these BM131, BS161, and the BS side light reflection film 162. The width 162x of the BS side light reflection film 162 is configured to be narrower than the width 161x of the BS161. This is to prevent the BS side light reflection film 162 from being visible and degrading the display quality when the display screen is observed obliquely.

[0092] As described above, the width 161x of the BS 161 is narrower than the width 131x of the light absorbing band of the BM 131 extending in the Y direction. The openings (pixel openings) Px of the BM 131 correspond to the pixels of the display screen, and even if a slight misalignment occurs between the BM 131 and the BS 161, the misalignment does not affect the size or position of the pixel openings Px. This is because.

[0093] For this reason, these widths 162x, 161x, and 131x are configured so that the width 131x of the light absorbing band extending in the Y direction of the BM 131 is the widest, the width 161x of the BS 161 is the next widest, and the width 162x of the BS-side light reflecting film 162 is the narrowest.

[0094] Like BM131, BS161 can be formed by dispersing black pigments with visible light absorption properties, such as carbon black or titanium black, in resin. In addition to these black pigments, organic pigments such as blue pigments can also be added. For example, BM131 can be formed by dispersing these pigments in a negative-tone photosensitive resin, applying it, and then exposing and developing it using photolithography technology.

[0095] The BS-side light-reflecting film 162 can be formed using a vacuum film-forming method such as vacuum deposition or sputtering, similar to the BM-side light-reflecting film 132. Also, similar to the BM-side light-reflecting film 132, the BS-side light-reflecting film 162 can be patterned using lift-off or photolithography techniques.

[0096] The material may also be the same as that of the BM-side light-reflecting film 132. That is, the BS-side light-reflecting film 162 may be made of a light-reflective metal thin film with a single-layer or multi-layer structure. For example, the BS-side light-reflecting film 162 may be made of a single-layer metal thin film made of aluminum or an aluminum alloy, or a single-layer metal thin film made of silver or a silver alloy, or may have a three-layer structure in which a thin film of conductive oxide is disposed on the side of a thin metal thin film made of silver or a silver alloy. Furthermore, these light-reflective metal thin films may be laminated between the BS 161 and the BS 161 with a thin film of titanium nitride or a thin film of titanium interposed therebetween.

[0097] The thickness thereof may be 0.15 to 0.8 μm, similar to that of the BM side light reflective film 132.

[0098] <Transparent resin layer 17> The transparent resin layer 17 protects the surface of the BM substrate 10, and is not necessarily provided. As will be described later, in the display devices 103 and 104 in which the liquid crystal layer 30 is driven pixel by pixel to display a screen, as in the fourth and fifth embodiments, when a common electrode is provided on the BM substrate, it is desirable to provide this transparent resin layer 17 on the BS-side light reflecting film 162 and place the common electrode via this transparent resin layer 17.

[0099] (Optical Module 20) As described above, the optical module 20 is a device that generates light used for screen display. As shown in Fig. 7 , the optical module 20 includes, in addition to the light-emitting elements 23, a substrate (optical module substrate) 21 that supports and arranges the light-emitting elements 23, a multilayer insulating layer 22, light-reflective electrodes 23a individually connected to the light-emitting elements 23, a common electrode 23b commonly connected to the plurality of light-emitting elements 23, a wavelength conversion layer 20RG, a transparent adhesive layer 24 that bonds the light-emitting elements 23 and the wavelength conversion layer 20RG, a prism sheet 25, and the like.

[0100] <Optical module board 21> The optical module substrate 21 may be transparent, but unlike the transparent substrate 1 of the BM substrate, it may also be opaque. For example, the optical module substrate 21 may be a silicon substrate on which CMOS elements (transistors, etc.) are disposed. The substrate 21 may also be a silicon substrate on which each light-emitting element 23 is formed by an LED crystal grown via a buffer layer.

[0101] A heat dissipation film 211 can be provided on the rear surface of the optical module substrate 21. There are no particular limitations on the material for 211 as long as it has good heat dissipation properties. For example, the heat dissipation film 211 can be made of a thin film made of aluminum or copper. This thin film can be formed by vapor deposition or sputtering.

[0102] <Light-emitting element 23> An LED (Light Emitting Diode) can be suitably used as the light emitting element 23. Among them, it is more preferable to use a monochromatic LED. As the monochromatic LED, a blue LED or a near-ultraviolet LED is particularly preferable.

[0103] LEDs are constructed by forming a pn junction between n-type and p-type semiconductors, and compounds such as aluminum gallium arsenide (AlGaAs), gallium arsenide phosphide (GaAsP), indium gallium nitride (InGaN) / gallium nitride (GaN) / aluminum gallium nitride (AlGaN), gallium phosphide (GaP), zinc selenide (ZnSe), and aluminum indium gallium phosphide (AlGaInP) are used in LEDs. When voltage is applied to both sides of this LED, electrons and holes recombine at the interface between the n-type and p-type semiconductors, generating light as this recombination occurs. This light-emitting interface is sometimes called the "active layer" or "light-emitting layer."

[0104] There are two types of LEDs: horizontal LEDs, in which the n-side electrode and p-side electrode are on the same side, and vertical LEDs, in which the n-side electrode and p-side electrode are on different surfaces (facing parallel surfaces) in the thickness direction of the LED. Either of these can be used. Also, mini LED chips with a size of 40 to 200 μm or micro LED chips with a size of 2 to 60 μm can be used.

[0105] The light emitting element 23 may be mounted by flip-chip mounting using a low melting point alloy, mounting using an anisotropic conductive film, or wire bonding using gold wire or the like.

[0106] In the first embodiment, a light-reflective electrode 23a is disposed on an optical module substrate 21 via a multilayer insulating layer 22. One light-reflective electrode 23a corresponds to one light-emitting element 23. Each light-emitting element 23 is connected to its corresponding light-reflective electrode 23a. Circuit wiring is formed on the multilayer insulating layer 22, and this circuit wiring is electrically connected to the light-reflective electrode 23a.

[0107] Furthermore, a transparent electrode is provided on the light-emitting elements 23, and this transparent electrode is electrically connected to a common electrode 23b via a contact hole. The common electrode 23b is electrically connected to all of the light-emitting elements 23, and by applying a voltage between this common electrode 23b and the light-reflective electrode 23a and applying a voltage to the light-emitting elements 23 between the transparent electrode and the light-reflective electrode 23a, the light-emitting elements 23 can be made to emit light. Note that, as described above, one light-reflective electrode 23a is connected to one light-emitting element 23, and therefore, each light-emitting element 23 can be made to emit light individually. Furthermore, the light emission intensity can be controlled individually for each light-emitting element 23.

[0108] Furthermore, since there is a 1:1 correspondence between the light-emitting elements 23 and the pixels of the display screen, i.e., the pixel openings Px of the BM substrate 10, it is possible to control the lighting and extinguishing of each light-emitting element 23 and also to control the light emission intensity, thereby controlling the display screen pixel by pixel and displaying the screen.

[0109] FIG. 8 shows a circuit diagram of a drive circuit for the light emitting element 23 of the optical module 20. S " is the source line, "23 G " indicates a gate line. CS " indicates the auxiliary capacitance, and the symbol "23 T1 " indicates a selection transistor, and "23 T2 " is the driving transistor In this circuit, the select transistor 23 T1 and power line 23VD A driving transistor 23 supplies a current to the light emitting element 23 from T2 Two transistors are required.

[0110] This circuit can employ an analog dimming method in which a variable resistor is further incorporated and the resistance value of the variable resistor is changed to adjust the magnitude of the current to the light-emitting elements 23. By adjusting the magnitude of the current to the light-emitting elements 23 in this way, the brightness of the light source light generated by each light-emitting element 23 can be controlled.

[0111] <Wavelength conversion layer 20RG> The wavelength conversion layer 20RG converts blue light emitted from the light emitting element 23, which is a blue-emitting LED, into pseudo-white light. In this embodiment, the wavelength conversion layer 20RG is laminated on the light emitting element 23 via a transparent adhesive layer 24. The transparent adhesive layer 24 may be, for example, a silicone adhesive.

[0112] Materials used for wavelength conversion can be divided into two categories: quantum dots, which are nanometer-sized semiconductor particles with quantum confinement effects (hereafter referred to as quantum dots), and inorganic phosphors (hereafter referred to as phosphors), which are represented by complex oxides and nitrides to which activators such as rare earth elements EU (europium), Ce (cerium), and Y (yttrium) have been added.

[0113] Compared to quantum dots, phosphors have a larger average particle size of 0.5 μm to 30 μm, but they are highly reliable in terms of heat resistance and light resistance, due in part to the manufacturing process undergoing high temperatures and pressures.

[0114] Examples of quantum dots include II-VI semiconductor compounds such as MgS, MgSe, MgTe, CaS, CaSe, CaTe, SrS, SrSe, SrTe, BaS, BaSe, BaTe, ZnS, ZnSe, ZnTe, CdS, CdSe, CdTe, HgS, HgSe, and HgTe, IIIV semiconductor compounds such as AlN, AlP, AlAs, AlSb, GaAs, GaP, GaN, GaSb, InN, InAs, InP, InSb, TiN, TiP, TiAs, and TiSb, and semiconductor crystals containing Group IV semiconductors such as Si, Ge, and Pb, as well as semiconductor compounds containing three or more elements such as InGaP. The size of quantum dots is, for example, within the range of 0.5 nm to 30 nm, and increasing the particle size shifts the converted light to longer wavelengths.

[0115] The wavelength conversion layer 20RG contains red conversion particles and green conversion particles to obtain red, green, and blue secondary light. The red conversion particles and green conversion particles applicable to the wavelength conversion layer 20RG can be appropriately selected from quantum dots or phosphors.

[0116] Red conversion particles refer to phosphor or quantum dot particles that can receive blue light and convert it to red wavelengths, while green conversion particles refer to phosphor or quantum dot particles that can receive blue light and convert it to green light.

[0117] In this example, both red conversion particles and green conversion particles are blended into a single wavelength conversion layer 20RG, but a red conversion layer containing red conversion particles and a green conversion layer containing green conversion particles may be provided separately. These red conversion layers and green conversion layers may be disposed on the same surface or may be stacked on top of each other. When stacked, it is preferable to arrange long-wavelength conversion particles, such as red, closer to the light-emitting element 23. It is preferable to arrange green conversion particles, which convert red light into green light, which has a shorter wavelength than red, farther from the light-emitting element 23 than the red conversion particles.

[0118] In this embodiment, a blue-emitting LED is used as the light-emitting element 23. However, when a near-ultraviolet-emitting LED is used as the light-emitting element 23, the wavelength conversion layer may contain red-conversion particles and green-conversion particles. Preferably, a red conversion layer, a green conversion layer, and a blue conversion layer containing red conversion particles and blue conversion particles, respectively, are provided. In this case, too, the wavelength conversion layer that converts light into light with a short wavelength is preferably disposed far from the light emitting element 23. That is, the order from the light emitting element 23 is the red conversion layer, the green conversion layer, and the blue conversion layer.

[0119] The wavelength converting layer 20RG can be formed as a dispersion in which wavelength converting particles are dispersed in a resin that has excellent heat resistance and light resistance. In addition to the wavelength converting particles and resin, transparent light scattering particles can also be blended.

[0120] Examples of resins used in the dispersion include silicone resins, epoxy resins, phenolic resins, polycarbonate resins, acrylic resins, polynorbornene resins, modified resins thereof, and hybrid resins.

[0121] The light-scattering particles may be any of those described above as transparent particles to be blended into the light-scattering layer 14. That is, they are particles having a particle diameter larger than the wavelength of visible light and a refractive index different from that of the resin. Specific examples include silica particles and zinc oxide particles having an average particle diameter of 1.0 to 3.0 μm, and particles of resins such as acrylic, styrene, urethane, nylon, melamine, and benzoguanamine.

[0122] The wavelength-converting layer 20RG can be formed by mixing the resin, wavelength-converting particles, and light-scattering particles in a monomer or an organic solvent to form a liquid dispersion, which is then printed. Alternatively, the wavelength-converting layer can be formed by applying and curing the dispersion using a device such as a spin coater, slit coater, curtain coater, or inkjet.

[0123] In addition, when using a phosphor as the conversion particles, it is also possible to use, for example, an alkali-soluble photosensitive polymer resist as the resin, and apply a dispersion liquid (dispersion) in which the phosphor is dispersed in this polymer resist, thereby forming a patterned wavelength conversion layer using photolithography techniques.

[0124] <Prism sheet 25> The prism sheet 25 widens the emission direction of the light source light emitted from the light emitting element 23. The prism sheet 25 can be manufactured, for example, by embossing a transparent resin sheet. It can also be manufactured by injection molding a transparent resin. A resin with a high refractive index is desirable as the transparent resin, and for example, an acrylic resin can be used.

[0125] [Second embodiment] Next, a display device 101 according to a second embodiment uses an optical module 20A shown in Fig. 10 instead of the optical module 20 according to the first embodiment, and is otherwise similar to the display device 100 according to the first embodiment. Fig. 9 shows the display device 101 according to the second embodiment.

[0126] This optical module 20A is configured by arranging multiple light-reflective metal containers 26 as its light-emitting elements. Each metal container 26 houses a light-emitting element 23 consisting of a blue LED wire-bonded with gold wire, and a wavelength conversion layer 20RG in which both red conversion particles and green conversion particles are dispersed is filled above the light-emitting element 23. Therefore, blue light generated from the light-emitting element 23 passes through the wavelength conversion layer 20RG, is converted into pseudo-white light, and is emitted. Note that the wavelength conversion layer 20RG may contain light-scattering transparent particles in addition to the red conversion particles and green conversion particles.

[0127] A prism sheet 25 is disposed on the plurality of metal containers 26 constituting the light emitting element so as to cover all of the plurality of metal containers 26 .

[0128] [Third embodiment] Next, a display device 102 according to a third embodiment uses a BM substrate 10A having a color filter layer 18 instead of the BM substrate 10 according to the first embodiment, and is otherwise similar to the display device 100 according to the first embodiment. Note that FIG. 11 shows the display device 101 according to the third embodiment, and FIG. 12 shows the BM substrate 10A. Also, FIG. 13 shows pixel openings 18 colored in various colors by the color filter layer 18. 11 ,18 12 14 is an explanatory diagram for explaining the arrangement of the pixel openings 18 colored in each color. 11 ,18 12 15 is an explanatory diagram for explaining the arrangement of the pixel openings 18 colored in each color by superimposing these. 11 ,18 12 ,..., an explanatory diagram for explaining the arrangement state of BM131 and BS161.

[0129] The color filter layer 18 colors the display light transmitted through the pixel apertures Px, enabling a color screen display. Such color filter layers 18 are well known and are typically disposed behind the BM 131 as viewed from the screen observer's side. However, in the third embodiment, as can be seen from FIGS. 11 and 12 , the color filter layer 18 is formed on the transparent substrate 11, and then the BM 131 is formed on the color filter layer 18, so that the color filter layer 18 is disposed on the screen observer's side of the BM 131. When the color filter layer 18 is formed on the BM 131, the surface of the BM 131 has irregularities. However, when the color filter layer 18 is formed on the transparent substrate 11, the surface of the transparent substrate 11 is smooth, which has the advantage of making the film thickness of the color filter layer 18 uniform and facilitating uniform coloring of transmitted light. Furthermore, since the BM-side light-reflecting film 132 is laminated on the surface of the BM 131 facing the optical module 20, there is a risk that the light-reflecting performance of the color filter layer 18 may be impaired if the color filter layer 18 is disposed on the BM-side light-reflecting film 132. In contrast, if the color filter layer 18 is disposed on the screen observer side of the BM 131, it is possible to take advantage of the light-reflecting performance of the BM-side light-reflecting film 132 and improve the light utilization efficiency of the light source light.

[0130] The color filter layer 18 is made up of color filters 18 having different colors. 11 ,18 12 As mentioned above, the color filter 18 11 ,18 12 , ... color the display light passing through the pixel aperture Px, and determine the color of the display screen. 11 ,18 12 , . . . are arranged in the pixel aperture Px, and typically use color filters of the three primary colors of light (red, green, and blue).

[0131] As will be described later with reference to FIGS. 13 to 15, in the third embodiment, each colored filter 18 04 ,18 05, . . . have a linear shape extending in the Y direction, and therefore, each of the colored filters 18 04 ,18 05 , . . . intersect with the BM 131 and overlap with the BM 131 at the intersection position, but do not overlap with the BM 131 at the pixel opening. Therefore, for the sake of convenience, the colored filters corresponding to each pixel opening are labeled "18 11 "," 18 12 Therefore, these symbols indicate the respective pixel openings Px, and also indicate the colored filters arranged in the respective pixel openings Px.

[0132] And colored filters 18 01 Since the pixel openings 18 in the first column are linearly aligned in the Y direction, 11 ,18 21 ,18 31 ,...This color filter 18 01 The pixel opening 18 three columns later has the same color. 14 ,18 24 ,18 34 ,‥also color filter 18 01 In this embodiment, both are red.

[0133] Colored Filter 18 01 Adjacent colored filters 18 02 is green. Therefore, the first Pixel openings 18 belonging to a column 12 ,18 22 ,18 32 , . . . are green. The pixel opening 18 three columns after that 15 ,18 25 ,18 35 ,‥is also green.

[0134] In addition, color filters 18 02 Adjacent colored filters 18 03 Therefore, the pixel openings 18 belonging to the first column are blue. 13 ,18 23 ,18 33 , ‥ are also green. Of course, the pixel opening 18 three columns after that16 ,18 26 ,18 36 ,‥is also green.

[0135] By the way, these color filters 18 04 ,18 05 The layers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 39, 38, 39, 4

[0136] Examples of red organic pigments that can be used in red colored filters (red filters) include CI Pigment Red 7, 14, 41, 48:2, 48:3, 48:4, 81:1, 81:2, 81:3, 81:4, 146, 168, 177, 178, 179, 184, 185, 187, 200, 202, 208, 210, 246, 254, 255, 264, 270, 272, and 279. In addition to the red pigment, a yellow pigment or an orange pigment can also be used in the red filter.

[0137] Examples of yellow pigments include CI Pigment Yellow 1, 2, 3, 4, 5, 6, 10, 12, 13, 14, 15, 16, 17, 18, 24, 31, 32, 34, 35, 35:1, 36, 36:1, 37, 37:1, 40, 42, 43, 53, 55, 60, 61, 62, 63, 65, 73, 74, 77, 81, 83, 93, 94, 95, 97, 98, 100, 101, 104, 106, 108, 109, 110, 113, 114, 115, 116, 117, 118, 119, 120, 121, 122, 123, 124, 125, 126, 127, 128, 129, 130, 131, 132, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 143, 144, 145, 146, 147, 148, 149, 150, 151, 152, 153, 154, 155, 156, 157, 158, 159, 160, 161, 162, 163, 164, 165, 166, 167, 168, 169, 17 17, 118, 119, 120, 123, 126, 127, 128, 129, 147, 151, 152, 153, 154, 155, 156, 161, 162, 164, 166, 167, 168, 169, 170, 171, 172, 173, 174, 175, 176, 177, 179, 180, 181, 182, 187, 188, 193, 194, 199, 198, 213, 214, etc.

[0138] Examples of green organic pigments that can be used in green colored filters (green filters) include green pigments such as CI Pigment Green 7, 10, 36, and 37. Furthermore, halogenated zinc phthalocyanine green pigments and halogenated aluminum phthalocyanine green pigments can also be suitably used in green filters.

[0139] The green filter may contain the above-mentioned yellow pigment in addition to the green pigment.

[0140] Examples of blue organic pigments that can be used in blue colored filters (blue filters) include blue pigments such as CI Pigment Blue 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 22, 60, and 64.

[0141] The blue filter may contain a violet pigment in addition to the blue pigment, such as CI Pigment Violet 1, 19, 23, 27, 29, 30, 32, 37, 40, 42, and 50.

[0142] The transparent photosensitive resin in which these organic pigments are dispersed is preferably a transparent resin having a transmittance of 90% or more in the visible range, and more preferably an alkali-soluble photosensitive resin containing a resin precursor.

[0143] The transparent photosensitive resin may be, for example, a linear polymer having reactive substituents such as hydroxyl groups, carboxyl groups, and amino groups, and a reactive group such as isocyanate groups, aldehyde groups, and epoxy groups. Examples include resins in which a photocrosslinkable group such as a (meth)acryloyl group or a styryl group is introduced into the linear polymer by reacting a (meth)acrylic compound having a substituent or cinnamic acid.

[0144] Furthermore, examples of monomers and oligomers that are precursors of transparent resins include various acrylic acid esters and methacrylic acid esters such as 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, cyclohexyl (meth)acrylate, polyethylene glycol di(meth)acrylate, pentaerythritol tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tricyclodecanyl (meth)acrylate, melamine (meth)acrylate, and epoxy (meth)acrylate, as well as (meth)acrylic acid, styrene, vinyl acetate, (meth)acrylamide, N-hydroxymethyl (meth)acrylamide, and acrylonitrile. These can be used alone or in combination of two or more.

[0145] These pigments are mixed in a range of 15% by mass to 60% by mass with respect to a transparent photosensitive resin or a precursor thereof to prepare a coating liquid, which is then applied to the first black matrix 14 to form a coating film, and then the coating film is exposed to light through a photomask and subsequently developed with an alkaline solution to form a colored filter 18. 01 ,18 02 ,‥ can be formed.

[0146] [Fourth embodiment] Next, a fourth embodiment of the present invention will be described with reference to Figures 16 to 18. A display device 103 according to this fourth embodiment uses a liquid crystal drive substrate 40 in addition to a BM substrate 10B and an optical module 20. A liquid crystal layer 30 is interposed between this liquid crystal drive substrate 40 and the BM substrate 10A, and this liquid crystal layer 30 is driven pixel by pixel to display an image. The optical module 20 is disposed behind the liquid crystal drive substrate 40, and light from the light source emitted from this optical module 20 passes through the liquid crystal drive substrate 40, the liquid crystal layer 30, and the BM substrate 10B in this order, to display an image on the surface of the BM substrate 10A.

[0147] Like the BM substrate 10A according to the third embodiment, the BM substrate 10B according to the fourth embodiment has a color filter layer 18. In addition, the BM substrate 10B has an alignment film that aligns the liquid crystal layer and a polarizing film.

[0148] FIG. 16 is an explanatory cross-sectional view of a display device 103 according to the fourth embodiment, and FIG. 17 is an explanatory cross-sectional view of a liquid crystal driving substrate 40 thereof.

[0149] 17, the liquid crystal driving substrate 40 includes a transparent substrate (transparent substrate of the liquid crystal driving substrate) 41, an insulating layer 42, a common electrode 43, an insulating layer 44, and a pixel electrode 45. In addition, an alignment film and a polarizing film (not shown) are provided on the liquid crystal driving substrate 40. The common electrode 43, the insulating layer 44, and the pixel electrode 45 may be formed on both sides of the insulating layer 44 as a wiring substrate base material.

[0150] The pixel electrodes 45 correspond one-to-one to the pixel openings Px. At least one thin film transistor is connected to each pixel electrode 45, and by driving this thin film transistor, a voltage can be applied to each pixel electrode 45. By applying a voltage to each pixel electrode 45 in this way, the liquid crystal layer 30 can be driven for each pixel electrode 45, and the screen can be displayed by controlling each pixel opening Px, i.e., each pixel.

[0151] In this embodiment, the liquid crystal layer 30 is driven by the FFS (fringe field switching) method, which is driven by the fringe electric field between the pixel electrode 45 and the common electrode 43. When using a VA (vertical alignment) type liquid crystal that is driven by an electric field between the BM substrate 10B and the liquid crystal drive substrate 40, it is desirable to provide a common electrode on the BM substrate 10B instead of the common electrode 43, and to apply a voltage between this common electrode on the BM substrate 10B and the pixel electrode 45 on the liquid crystal drive substrate 40.

[0152] 18 shows a circuit diagram of a circuit for applying a voltage to the pixel electrode 45. As shown in this diagram, one pixel electrode 45 is connected to one thin film transistor 45. T and one thin film transistor 45 T By controlling the voltage Vcc, it is possible to control one pixel electrode 45. In other words, it is possible to control each pixel electrode 45 individually.

[0153] In this circuit, the source line 45 S The video signal from the gate line 45 G Upon receiving a selection signal from the pixel electrode 45, a liquid crystal driving voltage is applied to the pixel electrode 45, and the liquid crystal layer 30 is driven. CS " indicates the auxiliary capacitance, and the symbol "45 C " indicates the storage capacitance line, and these storage capacitance 45 CS and auxiliary capacitance line 45 c The formation of may be omitted.

[0154] In the fourth embodiment, an optical module similar to the optical module 20 according to the first embodiment is used as the optical module. As described above, the light-emitting elements 23 built into the optical module 20 correspond one-to-one to the pixel openings Px, and the on / off or emission brightness of each light-emitting element 23 can be controlled. However, in the fourth embodiment, the display screen can be controlled by the liquid crystal drive substrate 40, so the light-emitting elements 23 do not need to correspond one-to-one to the pixel openings Px. In other words, even if the number of light-emitting elements 23 built into the optical module 20 is smaller than the number of pixel openings Px of the BM substrate 20B, the display screen can be controlled pixel by pixel.

[0155] A display device 104 according to a fifth embodiment, which will be described next, uses an optical module 20B incorporating light emitting elements 23 whose number is less than the number of pixel openings Px.

[0156] [Fifth embodiment] A display device 104 according to the fifth embodiment is configured to be able to control the light intensity for each area to display on the screen using local dimming technology, and is otherwise similar to the display device 103 according to the fifth embodiment. That is, as shown in Fig. 19, this display device 104 is configured by arranging, in this order, a BM substrate 10B having a color filter layer 18, a liquid crystal layer 30, a liquid crystal driving substrate 40, and an optical module 20B.

[0157] The optical module 20B is configured by arranging a plurality of light-emitting units 20a, and the intensity of the light source light emitted by each of the plurality of light-emitting units 20a can be controlled. A partition 20b is provided at the boundary between the light-emitting units 20a to block light. For example, a partition 20b1 is provided at the boundary between the light-emitting units 20a1 and 20a2. Since the partition 20b1 is provided between the light-emitting units 20a1 and 20a2, each light-emitting unit 20a can be controlled, and the light generated by this light-emitting unit 20a is prevented from mixing with the light generated by the adjacent light-emitting unit 20a. For example, when the light-emitting element 23 of the light-emitting unit 20a1 is turned on and the light-emitting element 23 of the adjacent light-emitting unit 20a2 is turned off, the light source light generated by the light-emitting unit 20a1 does not exit beyond the partition 20b1.

[0158] Therefore, if the area of ​​the display screen corresponding to each light-emitting unit is defined as a display area 100a, it is possible to control the brightness of the display light of the corresponding display area 100a by controlling the light intensity of the light-emitting unit 20a. Of course, this display area 100a can include a large number of pixel openings Px.

[0159] For example, in the liquid crystal display device 104 shown in Fig. 19, when focusing on the left-right direction (X direction) in the figure, the display area corresponding to light-emitting unit 20a1 is indicated by the symbol "100a1." Therefore, if the image displayed in this display area 100a1 is a low-brightness image, the light intensity of light-emitting unit 20a1 can be reduced. By using local dimming technology to control the light intensity for each light-emitting unit 20a in this way, it is possible to effectively utilize the light emitted from the light-emitting elements and improve the light utilization efficiency.

[0160] Moreover, because the optical module 20B is controlled for each light-emitting unit 20a, there is no direct relationship between the number of light-emitting elements included in the optical module 20B and the number of pixels on the display screen. Therefore, the number of light-emitting elements included in the light-emitting unit 20a can be made smaller than the number of pixel openings Px included in the display area, making it possible to make the number of light-emitting elements included in the entire optical module 20B smaller than the number of pixels on the entire display screen.

[0161] Incidentally, in order to control the light intensity for each light-emitting unit 20a, the following method can be adopted.

[0162] That is, first, the first method is to control the brightness of the light source light emitted from each light-emitting element 23 by adjusting the magnitude of the current to the light-emitting element 23 included in each light-emitting unit 20a, and as a result, it is possible to control the brightness of the light source light for each light-emitting unit 20a.

[0163] In addition, by controlling the lighting time of the light-emitting elements 23 included in the light-emitting units 20a, it is also possible to select a PWM (Pulse Width Modulation) driving method that adjusts the brightness of the light source light for each light-emitting unit 20a, thereby controlling the brightness of the light source light for each light-emitting unit 20a.

[0164] Furthermore, the light-emitting units 20a may incorporate a drive control circuit that selects light-emitting elements 23 to be emitted from the plurality of light-emitting elements 23 included in the light-emitting units 20a and applies voltage to the selected light-emitting elements 23. By causing some of the selected light-emitting elements 23 to emit light in this manner, it is possible to control the light intensity for each light-emitting unit 20a.

[0165] The partitions 20b are disposed at the boundaries between the light-emitting units 20a to prevent light from passing through. Therefore, the partitions 20b can be black, which absorbs light. Furthermore, the surfaces of the partitions 20b can be made light-reflective, so that the light source light incident from each light-emitting unit 20a can be reflected back toward that light-emitting unit 20a. Making the partitions 20b light-reflective in this way can further improve the light utilization efficiency of the light source light.

[0166] The black partition walls 20b can be made of a resin composition containing a black pigment such as carbon black or titanium black. For example, the partition walls 20b can be formed by blending the black pigment into a photoresist, applying the photoresist, and then exposing and developing the photoresist. Alternatively, the partition walls 20b can be formed by printing black ink.

[0167] The light-reflective partition wall 20b may be formed by attaching a light-reflective metal thin film to the surface of a resin partition wall. The light-reflective metal thin film may be any of the metal thin films described above as constituting the BM-side light-reflecting film 132 and the BS-side light-reflecting film 132. For example, the metal thin film may be aluminum or an aluminum alloy, or silver or a silver alloy. Alternatively, the metal thin film may have a multilayer structure.

[0168] In addition to the light-reflective partition wall 20b, by disposing a light-reflective member inside the optical module 20B, it is possible to improve the light utilization efficiency of the light source light.

[0169] It is also possible to arrange light-reflective metal containers 26 (see FIG. 10) each containing a light-emitting element 23 and a wavelength conversion layer 20RG to form a light-emitting unit 20a. [Explanation of symbols]

[0170] 100,101,102,103,104:Display device 100a: Display area 10, 10A, 10B: Black matrix substrate (BM substrate) 11: Transparent substrate of BM substrate 12: Transmittance adjustment layer 131: Black matrix (BM) Px: Pixel opening 132: Black matrix side light reflective film (BM side light reflective film) 14:Light scattering layer 15: Flattening layer 161: Black Stripe (BS) 162: Black stripe side light reflective film (BS side light reflective film) 17: Transparent resin layer 18: Color filter layer 18 11 ,18 12 , ‥: Colored filters placed at the pixel apertures 20, 20A, 20B: Optical module 20a: Light-emitting unit 20b: Bulkhead 21: Optical module substrate 211: Heat dissipation film 22: Insulating layer 23: Light-emitting element 23a: Light-reflective electrode 23b: Common electrode twenty three CS :Auxiliary capacity 23 G :Gate line 23 S :Source line 23 T1 :Selection transistor 23 T2 : Drive transistor 23 VD :Power line 24: Transparent adhesive layer 25: Prism sheet 26: Metal container 20RG: wavelength conversion layer 30: Liquid crystal layer 40: LCD drive board 41: Transparent substrate for LCD drive board 42: Insulating layer 43: Common electrode 44: Insulating layer 45: Pixel electrode 45 C : Auxiliary capacitance line 45 CS :Auxiliary capacity 45 G :Gate line 45 S :Source line 45 T : Thin film transistor

Claims

1. A display device is configured by overlapping a black matrix substrate and an optical module, and displays a screen by controlling the light source of the optical module, the black matrix substrate includes a black matrix (BM) and black stripes (BS), and the BS is disposed closer to the optical module than the BM; the BM has a shape in which light absorbing bands extending in two directions perpendicular to each other are arranged in a lattice pattern, and the openings are pixel openings corresponding to pixels of a display screen; the BS has a shape in which light absorption bands extending in a certain direction are arranged in parallel, and the direction in which the light absorption bands extend coincides with one of two directions in which the BM extends, and both are overlapped in a positionally aligned manner; A light reflective film (BS-side light reflective film) is laminated on the optical module side surface of this BS, A display device characterized in that a light-reflecting film (BM-side light-reflecting film) is laminated on the optical module side surface of the light-absorbing band that is not overlapped with the BS, among the light-absorbing bands extending in two directions of the BM.

2. 2. The display device according to claim 1, wherein the width of the light absorbing band overlapped by the BS, among the light absorbing bands extending in two directions of the BM, is wider than the width of the BS.

3. 3. The display device according to claim 1, wherein the width of the BS-side light reflecting film is narrower than the width of the BS.

4. A display device according to any one of claims 1 to 3, characterized in that, of the light absorbing bands extending in two directions of the BM, the width of the BM-side light reflecting film is narrower than that of the light absorbing band on which the BM-side light reflecting film is laminated.

5. 5. The display device according to claim 1, wherein the BS-side light-reflecting film is made of a metal thin film of aluminum or an aluminum alloy laminated via a titanium film or a titanium nitride film.

6. 5. The display device according to claim 1, wherein the BS-side light-reflecting film has a three-layer structure, and the middle layer is made of a metal thin film of silver or a silver alloy.

7. 7. The display device according to claim 1, wherein the black-and-matrix-side light-reflecting film is made of a metal thin film of aluminum or an aluminum alloy laminated via a titanium film or a titanium nitride film.

8. 7. The display device according to claim 1, wherein the black-and-bearing-side light-reflecting film has a three-layer structure, the middle layer of which is made of a metal thin film of silver or a silver alloy.

9. 9. The display device according to claim 1, wherein the black matrix substrate is provided with a transmittance adjusting layer on the viewer side of the BM.

10. 10. The display device according to claim 9, wherein the transmittance adjusting layer is made of a dispersion in which at least carbon is dispersed in a transparent resin.

11. 11. The display device according to claim 1, wherein the black matrix substrate includes a light scattering layer between the BM and the BS.

12. 12. The display device according to claim 11, wherein the light scattering layer is made of a dispersion of transparent particles, carbon, and a transparent resin.

13. 13. The display device according to claim 1, wherein the black matrix substrate comprises a color filter layer that colors transmitted light.

14. 14. The display device according to claim 1, wherein a plurality of light-emitting elements are arranged inside the optical module.

15. 15. The display device according to claim 14, wherein the light emitting element is a light emitting element that emits monochromatic light of blue or near ultraviolet.

16. 16. The display device according to claim 15, wherein the light emitting element is an LED.

17. The black matrix substrate is provided with a color filter layer that colors transmitted light. the color filter layer has a plurality of color filters having different colors, 17. The liquid crystal display device according to claim 15, further comprising a wavelength conversion layer between the light emitting element and the colored filter, the wavelength conversion layer converting light emitted from the light emitting element into green light or red light.

18. A display device as described in any one of claims 1 to 17, characterized in that a liquid crystal layer and a liquid crystal driving substrate are provided between the black matrix substrate and the optical module, and the liquid crystal layer is driven between the black matrix substrate and the liquid crystal driving substrate.

19. The optical module is configured by arranging a plurality of light-emitting units, 19. The display device according to claim 18, wherein when a region of a display screen corresponding to a single light-emitting unit is defined as a display area, the display area includes a plurality of the pixel openings.

20. 18. The display device according to claim 14, wherein the light emitting elements correspond to the pixel openings in a one-to-one correspondence.

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